Friday, 10 July 2015

Pipe and Cistern Shortcuts for bank po and clerk

Pipe And Cistern questions for Bank Exams

Pipe And Cistern questions for Bank Exams:In every bank exams ,under quantitative section,there will be at least one question on" pipe and cistern". Solving these type of question is similar to solving Work and Time problem.An average student can solve pipe and cistern problems. But as you know, in bank exams time management matters a lot.We are sharing some important Pipe and Cistern Shortcuts.Hope you will find it useful in upcoming exams.

Pipe and cistern important shortcut formulas

1.If two pipes A and B

A can fill a tank in x hrsand B can fill the same tank in y hrsIf both pipes are opened simultaneously ,then time taken to fill the tank is

Work done by both pipes together in 1hr=1/x +1/y2.If two pipes A and BA can fill a tank in x hrsand B can empty the same tank in y hrsIf both pipes are opened simultaneously ,then time taken to fill the tank is =

Work done by both pipes together in 1hr=1/x -1/y3.If three pipes A ,B and CA can fill a tank in x hrsB can fill the same tank in y hrand C takes z hrs for filling the same tank.If three pipes are opened simultaneously ,then time taken to fill the tanks is

Work done by three pipes together in 1hr=1/x +1/y +1/zExample: A can fill the tank in 28hrsB can fill the tank in 14 hrsand C takes 7hrs.If all three pipes are opened simultaneously ,how long it will take to fill the tank?Solution:time taken=(28*14*7*)/(28*14 + 14*7 + 28*7)To solve this quicker find out LCM(28,14,7)we get 28Time taken =28/(28/28 + 28/14 + 28/7)=28/(1+2+4)=28/7=44.If A can fill a tank in x hrs,B can fill the same tank in y hr and C takes z hrs for emptying the same tank.If three pipes are opened simultaneously time taken to fill the tank is=

Work done by three pipes together in 1hr=1/x +1/y -1/zExample: A can empty the tank in 28 hrs, B can fill the tank in 14 hrs, and C takes 7 hrs for filling.If all three pipes are opened simultaneously ,how long it will take to fill the tank?Solution:time taken=(28*14*7*)/(28*14 - 14*7 + 28*7)To solve this quicker find out LCM(28,14,7)we get 28Time taken =28/(-28/28 +28/14 + 28/7)=28/(-1+2+4)=28/5=5.6 hrs=5 hr 36 minutes